Full Idea
Among the forces cultivated by morality was truthfulness: this eventually turned against morality, discovered its teleology, its partial perspective.
Gist of Idea
Truth was given value by morality, but eventually turned against its own source
Source
Friedrich Nietzsche (The Will to Power (notebooks) [1888], §015)
Book Reference
Nietzsche,Friedrich: 'The Will to Power', ed/tr. Kaufmann,W /Hollingdate,R [Vintage 1968], p.10
A Reaction
Just as 'duty' is said to have withered in modern times, because its religious underpinning has been lost, so this gives an account of the decline of the value of truth. It is still left to us to assert the value of truth, perhaps as the only value.